In the early 1900s, cervical cancer was the leading cause of cancer death for women. Even today, after nearly 100 years of continued medical research and development, cervical cancer continues to be the leading cause of cancer death for women in developing countries. These deaths are completely unnecessary because up to 90% of the most common types of cervical cancer may be prevented if identified early and treated. The present invention facilitates this early identification and subsequent treatment.
In spite of the ability of modem medical practitioners to effectively eradicate most types of cervical cancer, it is estimated that 100,000 new cases of cervical cancer in the United States go undetected every five years. The same characteristics of cervical cancer that make it relatively easy to treat once identified contribute to the difficulty in its detection. In its early stages of development, cervical cancer grows contiguously in localized, defined sites and does not interfere with other normal bodily functions. Thus, at these early stages, cervical cancer can be relatively asymptomatic and can continue to grow and progress for years with little indication other than minor, localized bleeding which can be dismissed as normal "spotting." Left unchecked for a year or more, cervical cancer can spread beyond the cervix without warning. At this point, once detected, the cancer may be so advanced that it may likely be untreatable and may ultimately lead to the patient's death.
Conversely, if detected early there are two effective forms of treatment for removing abnormal tissue from the cervix. In one procedure, the abnormal tissue is removed from the cervix in a cryosurgical procedure wherein the surface of the cervix is frozen. Alternatively, abnormal cervical tissue can be cauterized with a heated surgical apparatus. Both treatments are commonly performed in a doctor's office on an out-patient basis following a confirming biopsy. Post-surgical impact on the patient is relatively minor and short lasting.
The key to successful eradication of cervical cancer is early detection. For the last 50 years, a safe and effective cervical cancer-screening test has been available which can detect very early changes in cervical tissues long before any other symptoms develop. Known as the Pap Screening Test, or "Pap Smear," this test is a microscopic examination of a prepared glass slide containing a smear or sample of cells collected from the opening and outer portion of a patient's cervix by a healthcare professional during a pelvic exam.
The Pap-screening test is relatively simple and takes only a few minutes to perform. A physician or other healthcare professional inserts a special instrument known as a speculum into the patient's vagina to hold the vaginal walls apart so that the surface of the cervix can be directly observed and accessed. The lining or surface of the cervix is made up of millions of tiny cells. A sample of these cells is collected or "harvested" by the physician or healthcare professional utilizing a tiny spatula-like instrument or swab to scrape or rub cells from the cervical oz, from the surrounding cervical fornix, or from any suspicious-looking or abnormal areas on the cervix. These harvested cells are transferred directly to a glass slide where they are "smeared" into a thin layer, which is then stained and viewed under a microscope. Typically, the smeared glass slide is sent to a professional clinical laboratory for the microscopic examination. However, the slide can also be examined in the physician's office. Sometimes abnormal or pre-cancerous cells develop in the cervical lining, and, after staining, these cells can be readily identified under the microscope. If identified, these pre-cancerous changes, called "displasia," justify further testing, which may include a surgical "biopsy" wherein a small piece of tissue from the suspicious area is collected and examined. Because these pre-cancerous changes can grow and spread and may lead to cancer if left untreated, a positive biopsy result may justify removal of the abnormal cervical tissue.
More recently, an improved Pap-screening test has been developed utilizing the same cervical cell-collecting procedures as previously described, but adding the additional step of suspending the collected cells in a solution prior to making the smear on the glass slide. The cell suspension is sent to the laboratory to be read, whereupon the laboratory pathologist spins or centrifuges the suspension to deposit the cells in a thin, single cell layer on the slide. This procedure eliminates cell clumping and provides the pathologist with a smear that is easier to read correctly, thereby reducing the number of false positive test results.
In spite of the Pap-screening test's 50-year record of safety and accuracy, at least 35% of women in the United States between the ages of 15 and 44 do not schedule a regular visit for this vital screening exam. Thus, patient noncompliance is the biggest issue that must be overcome in order to reduce the incidence of cervical cancer. Presently, medical professionals recommend an annual Pap-screening test for every sexually active women up to age 70. Monogamous women with up to three normal Pap-screening tests in a row can decrease the recommended screening interval to once every three years. In spite of these recommendations, cervical cancer continues to exhibit two age-related peaks in the susceptible population for women in their 20s and again in their 50s. If identified early during the in situ stage before the cancer has invaded other tissues, then this completely unnecessary disease can be eliminated by resecting the cancerous tissue from the cervix. Nonetheless, patient compliance remains the biggest obstacle to this objective because even though the Pap-screening test is relatively noninvasive and quick, it remains physically and psychologically uncomfortable for most female patients. Compounding matters, in today's modem world, it is becoming increasingly more difficult for women to fit medical appointments into their busy daily schedules. Further compounding matters, socioeconomic pressures may make it difficult if not impossible for many women to afford the cost of a medical visit and subsequent laboratory analysis. In developing countries, the simple absence of trained healthcare professionals and laboratory facilities may make these screening tests impossible to administer to the population at large.
Accordingly, it is a primary objective of the present invention to provide effective methods and apparatus that will facilitate the collection or harvesting of endocervical cells making up the lining of the cervical mucosa or mucus membranes in a manner that will readily interface with existing cervical cancer-screening laboratory techniques.
It is an additional object of the present invention to provide effective methods and apparatus for cervical cancer-screening tests which can be self-administered without the need for direct cervical observation or access or without the assistance of healthcare professionals.
It is a still further object of the present invention to provide cervical cancer self-screening methods and apparatus which are inexpensive to produce and distribute and which can be made widely available to the consuming public.